Coated



MarcHlO, 1925- A. s. MERRILL COATED, CELLULAR STRUCTUREAND METHOD OF MAKING THE SAME M2273 17/2717 Z7. Hmwzfl Filed Nov a, 192

Patented Mar. Q, 1925.

UNITED STATES PATENT OFFICE.

ALLAN B. MERRILL, or AKRON, OHIO, AssIGNoa r THE B. r. eoonnrcn COMPANY, on NEW YORK, N. Y., A CORIORATIO'N on NEW re ax.

COATED, CELLULAR STRUCTURE AND METHOD OF MAKING THE SAME.

Application filed November 8, 1923. Serial No. 673,406;

Method of Making the Same, of which the following is a specification.

This invention relates to coated cellular structures, such, for example, as'a spongerubher inking roll coated with a soft, resilient material, for use in place of the rubber or gelatin rolls heretofore employed in printing presses. Where soft rubber has been employed as the surface material in such rolls it has deteriorated as; the result of absorption of the oil in inks having an oil base, and by some users it is found to be, because of its relative stiffness, less desirable 'as a surface material than the gelatin which has long been employed in that capacity. Where the roll has been formed in large part of inking roller composition such as glue and molasses, commonly called gelatin, on the other hand, the roll has been subject to objectionable deformation, especially in hot weather.

My general object is to provide a cellular body and a coating thereon, in which the coating and the body will be securely held together in an improved manner. A more specific object is to provide an improved inking roll or similar article in which soft resilience will be combined with durability.

Of the accompanying drawings:

Fig. 1 is a perspective view of parts of an inking roller embodying a preferred form of my invention, in process of manufacture.

Fig. 2 is a simlar view of the same at a later stage.

gig. 3 is a similar view of the finished ro Fig. 4 is a magnified section of conjoined elements of the roll.

In the practice of my method, inthe'v case of an inking roller such as is shown in the accompanying drawings, it being unders od that my invention is not limited to all of the steps of upon a roller-shaft 10, preferablyby cementing, a layer or windlng 11 of rubberized fabric adapted to serve as an anchorage for the body of the roll. A generally cylindriprocedure nor to all of the fea-, turesof construction described, I. secure cal body of sponge-rubber is then mounted upon and anchored to said fabric, preferably by winding thereon a semi-vulcanized and cemented sponge-rubber sheet 12, the winding operation being illustrated in Fig. 1, whereby said body is produced in laminated form.

In the semi-vulcanizing of the spongerubber sheet, as in ordinary practice, a film or skin of relatively dense rubber, 12 Fig. 1, which may be either substantially smooth and continuous or more or less pitted, is produced on each face of the sheet, and said skins, coming together in the wound body ofthe roll, together with an intervening layer of cement, when the latter is used, provide a spiral, strength-giving structure of relatively dense rubber within the roll, adapted, by distributing the strains resulting from force applied to the roller, to prevent excessive distortion of the sponge-rubber cell walls in any region of the roller which may be of less strength or density than another, and thereby to provide substantially uniform resilience at all radii of the roller, and this without excessively stiffsuing the latter. The construction of the roller in this respect is similar to that shown and claimed in my copending application Ser. No. 627,303, filed March 24, 1923.

When the vulcanized rubber sheet 12 has been completely wound upon the fabric layer 11, and the cement securing together the successive convolutions thereof is dried, the resulting structure is completely vulcanized, preferably by a wrapped cure, and is then given a true cylindrical form, preferably by surface abrading as shown at 13 Fig. 2, whereby the skin 12 (Fig. 1), is removed from the outer face of the structure, leaving exposed the underlying cellular rubber, with a multiplicity of the cells thereof, 15, 15, Fig. 4, opened on the outer face of the structure by the abrading operation.

A substantially cylindrical body of sponge-rubber being thereby produced which presents a pitted surface, a layer of gelatin 14, Fig; 3, is applied thereto, as by pouring it on in a heat-softened condition, and molded or otherwise given a true cylindrical form, the gelatin entering the recesses of said pitted surface and interlocking with the walls 16, 16, Fig. 4, of said recesses, thefications may shape of many of the recesses formed as described being such as to provide radial as well as circumferential interlocking of the rubber and gelatin. A very secure anchorage of the gelatin layer 14 upon the sponge-rubber body of the roll is thus provided. This outer gelatin layer 14 may be of any suitable relative thickness and might be considerably thinner than is indicated in the drawings.

The finished product, shown in Fig. 3, is a roll having a gelatin surface, with the desirable properties incident thereto, and having a durable, resilient body upon which the gelatin layer is effectively anchored. The gelatin layer, being relatively thin and anchored at all points, is not of such weight as to deform appreciably by gravity, even at relatively high temperature. Deforming forces in the mass of gelatin are less as compared with gelatin rolls heretofore used, not only because of the reduced quantity of gelatin employed, with a correspondin reduction of the force of gravity acting tiiereon, but also because the relatively large sponge-rubber body provides a very large area of contact between the gelatin and the underlying structure of the roll and also reduces the leverage with which gravity acts upon the gelatin to separate it from said underlying structure. 7

My improved roller provides the desired softness or minutely local deformability of gelatin for compensating fine or local irregularities in the surface to be inked, without great inequality of pressure against the roll at closely adjacent points, while the sponge-rubber body provides sufficient resilience to permit the roll to conform to the more extensive and less abrupt irregularities of the surface to be inked, under the aggregate force of said surface against the relatively large area of gelatin brought into contact therewith by the local deformation of the gelatin.

The final vulcanization of the wound structure of sponge-rubber sheet to true cylindrical form results in a thinning down of the terminal margin of the wound sheet toward its terminal edge, and in relieving the strain therein, so that said margin, being of reduced stiffness, is under comparatively httlestrain tending to straighten it and thus pull its terminal edge loose from the underying convolution of the sheet. This feature, which may also be provided in part by the final abrading of the structure 'to true cylindrical form, is particularly desirable in a gelatin covered roll, since the tensile strength of the gelatin is 'not such as greatly to asslst iii-preventing such straightening and detachment of said terminal margin.

It will be understood that yarious modibe made without departing from my invention.

I claim:

1. The method of making a coated, cellular structure which comprises vulcanizing a plastic, vulcanizable material having a blowing ingredient therein, removing a part of the vulcanized structure, whereby cells thereof are opened, and applying a coating to the pitted surface thus produced.

2. The method of making a coated, cellular structure which comprises producing a body of vulcanized sponge-rubber, removing a part thereof, whereby cells therein are opened, and applying a coating to the pitted surface thus produced.

3. The method of making an inking element which comprises producing a body of soft sponge-rubber, removing a part thereof, whereby a pitted surface is provided, and applying a layer of gelatin to said surface.

4. The method of making an inking element which comprises forming a laminated body of sponge-rubber sheet, opening cells thereof to provide a pitted surface, and securing thereon a layer of gelatin.

5. The method of making an inking roller which comprises forming a cylindrical, laminated body of sponge-rubber sheet, opening cells thereof at its surface, and applying a coating of gelatin to said surface and interlocking it with the walls of said opened cells.

6. The method of making an inking roller which comprises vulcanizing a sheet of soft sponge-rubber, winding said sheet upon a support and securing it in spiral form to produce a generally cylindrical body, removing material from said body whereby a pitted, substantially cylindrical surface is provided, and applying a coating of gelatin to said surface.

7. The method of making an inkin element which comprises forming a ho y of rubber of which substantially all parts are cellular, and securing directly thereon a layer of gelatin.

8. A cellular, coated structure comprising acellular body of vulcanized material hav- 'ng blown cells opened at its surface after ulcanization, and a coating of material thereon interlocked with the walls of said opened cells.

of soft sponge-rubber having cells thereof openedat its surface, and a layer of gelatin thereon interlocked with the walls of said opened cells.

11. An ink ng roller comprising a sub stantially cylindrical body of sponge-rubber havin' veins of relatively dense rubber curve about its axis and havin cells thereof o ned at its surface, an a layer of gelatm thereon interlocked with the walls of said opened cells.

12. An inking roller comprising a bod of wound, sponge-rubber sheet having ce 5 thereof opened at its surface, the outer terminal margin of the wound sheet being of l gradually reduced thickness toward its terminal edge, and a layer of gelatin on said body interlocked with the walls of said opened cells.

13. An inking element comprising a body of rubber of which substantially all parts 15 

